Risks include flooding, disruption to farming, and dangerous heat.

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These highways near New Orleans could be impacted by catastrophic flooding and sea-level rise.

PHOTOGRAPH BY GEORGE STEINMETZ, NATIONAL GEOGRAPHIC CREATIVE

A Tuesday report warning of dire economic consequences from climate change, from lost property to ruined crops, is the latest in a string of bipartisan efforts aimed at garnering public support to tackle the problem.

The new report is from a coalition of top U.S. political and economic leaders from the left, right, and center—including three former Treasury Department secretaries going back to the Nixon White House—and was reviewed by leading climate scientists.

"What we ultimately need is not just investment in resiliency to adapt to the outcomes we know are coming ... We need strong policy action to prevent the very worst outcomes, and I think that takes action by national government," said report co-chair Henry Paulson, who was Treasury secretary under George W. Bush.

Called "Risky Business," the 56-page report says risks posed by climate change over the next century include extensive property damage from catastrophic flooding and sea-level rise and severe disruption of agriculture in the American corn belt and Southeast. But it also said there is still time to act.

"If we continue on our current path, many regions of the U.S. face the prospect of serious economic effects from climate change," the report says. "However, if we choose a different path—if we act aggressively to both adapt to the changing climate and to mitigate future impacts by reducing carbon emissions—we can significantly reduce our exposure to the worst economic risks from climate change, and also demonstrate global leadership on climate."

As an example of how businesses might address climate-related risks, report co-chair and former New York Mayor Michael Bloomberg says he's moving one of his media company's key computer centers from lower Manhattan, which is at increased flooding risk, to upstate New York.

"I want to sleep at night," he said at a Tuesday press conference.

Report co-chair Tom Steyer, the retired founder of Farallon Capital Management, said that investors need to "get to a place where the calculation of a value of a company includes how they are handling this problem."

The report's GOP contributors were moderates, including Bloomberg and former Reagan Secretary of State George Shultz, and follows a series of recent warnings from groups that included middle-of-the-road Republicans.

Last month, 16 retired three- and four-star generals and admirals released a report calling climate change "a catalyst for conflict" that may lead to instability and disrupt global networks of trade and resources.

But global warming remains a politically polarized issue. Gallup's March 2014 poll found that just 42 percent of Republicans think most scientists believe global warming is occurring, compared with 82 percent of Democrats.

A report released in late May by the conservative-leaning U.S. Chamber of Commerce argued that the administration's new rule would cost $51 billion annually by 2030 and lead to a loss of 224,000 jobs.

Here are five of the rmost dire warnings from Tuesday's report:

1. A lot of coastal property and infrastructure is at risk.

The report warns that within the next 15 years, higher sea levels and storm surges will likely increase the average annual cost of coastal storms along the eastern seaboard and the Gulf of Mexico by somewhere between $2 billion to $3.5 billion. Adding in potential changes in hurricane rates and severity, the likely increase in average annual losses grows to up to $7.3 billion, bringing the total annual price tag for all coastal storms to $35 billion.

"If we stay on our current climate path," the report says, "some homes and commercial properties with 30-year mortgages in places in Virginia, North Carolina, New Jersey, Alabama, Florida, and Louisiana and elsewhere could quite literally be underwater before the note is paid off."

2. Farms face a significant decrease in crop yields.

Because of climate change, some midwestern and southern counties could see a decline in agricultural yields of more than 10 percent over the next 5 to 25 years, with a 1-in-20 chance of yield losses of more than 20 percent.

The report notes that food systems tend to be resilient and that higher temperatures may increase yields in the northern Great Plains. Still, there will be "risks for the individual farming communities" in the Midwest and South; such areas are likely to experience disruption.

3. Energy costs are set to rise.

Rising temperatures will likely require construction of up to 95 gigawatts of new power generation capacity over the next 5 to 25 years—roughly 200 coal or natural gas-fired power plants—thanks to increased cooling loads. That expansion will cost ratepayers up to $12 billion per year.

"Demand for electricity for air conditioning will surge in those parts of the country facing the most extreme temperature increases," the report warns, "straining regional generation and transmission capacity and driving up costs for consumers."

4. Expect more extreme heat.

Heat waves will become more likely in the next decades, especially in the Southwest, Southeast, and upper Midwest. This will threaten human health, labor productivity, and energy systems.

"By the middle of this century, the average American will likely see 27 to 50 days over 95°F each year—two to more than three times the average annual number of 95°F days we've seen over the past 30 years," the report warns. "By the end of this century, this number will likely reach 45 to 96 days over 95°F each year on average."

The report warns that by the end of the century, generally cool states like Oregon,

Washington, and Idaho could each have more days above 95°F each year than Texas has at present.

5. Extreme weather will be the "new normal."

The report warns that "the 'outlier' 1-in-100 year event today will become the 1-in-10 year event as the Earth continues to warm" and that "over time the extremes will become the 'new normal.'"

A warmer atmosphere will lead to stronger and more unpredictable storms. It will also make dry areas dryer and wet areas wetter.